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Screw-FIX Increaser - Ø 175-200mm

National Flues proudly introduces the Screw-FIX Increaser - Ø 175-200mm, a top-tier stainless steel adaptor designed for MI-FLEX flue systems. Engineered for reliability and safety, this product is perfect for connecting a rigid single wall flue system to a flexible flue liner. Whether you are upgra... More...
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At a Glance

  • High-quality 0.6mm 316L stainless steel construction
  • Increases the flue diameter by 25mm for a secure, seamless connection
  • Compliant with Building Regulations Document J and T600 temperature rating
  • Designed specifically for MI-FLEX 316 and 904 flexible flue liners
  • Suitable for use with wood (<20% moisture), gas, oil, and smokeless coal
Now only £37.99
Including VAT Buy with confidence. If you find this cheaper within 48 hours of checkout, we'll refund the difference.

 

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We Won't Be Beaten On Price

At National Flues, we continuously monitor competitor prices. This ensures that we consistently offer you the best deals on all our products. Here’s how we keep your costs low:

  • Daily Price Matching: Our team adjusts prices to ensure we stay competitive.
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Price Match Guarantee: If you find the same product cheaper within 48 hours, we’ll match it and refund the difference.

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Have Questions?
Phone: 01670 206999
Email: [email protected]

The Screw-FIX Increaser - Ø 175-200mm is a top-quality accessory expertly designed for use with MI-FLEX 316 and 904 flexible flue liners. This 0.6mm stainless steel adaptor serves as a transitional joint, increasing the diameter by 25mm from a single wall connecting flue system to a flexible flue liner. Compliant with Building Regulations Document J, it's suitable for appliances operating at temperatures up to 600°C (T600 designation), including those using wood with less than 20% moisture, smokeless coal, gas, and oil.

The increaser must be securely fitted within a masonry chimney and is designed to ensure a gas-tight seal, using fire cement, ceramic rope, or high-temperature sealant. Regular maintenance and sweeping by a competent person are advised, particularly for solid fuel appliances.

SKU: 25-175-MR

Technical Specifications
Material316L Stainless Steel
Diameter Increase25mm
Sizeu00d8 175-200mm
Temperature RatingUp to 600u00b0C (T600)
Compatible SystemsMI-FLEX 316 and 904 flexible flue liners
ComplianceBuilding Regulations Document J
Fuel CompatibilityWood (<20% moisture), Oil, Gas, Smokeless Coal
The Screw-FIX Increaser must be installed within a masonry chimney to meet regulatory requirements. Begin by ensuring that your flue system is thoroughly inspected and cleaned by a competent person. When fitting the increaser, secure it firmly using a recommended high-temperature sealing method such as fire cement, ceramic rope, or high-temperature sealant. Ensure all connections are gas-tight, and avoid using non-masonry enclosures such as timber or plasterboard. Follow the manufacturer’s guidelines closely and arrange for regular maintenance to sustain optimal performance.

The Screw-FIX Increaser is specifically designed for use with MI-FLEX 316 and 904 flexible flue liners.

The Screw-FIX Increaser is suitable for use with wood (less than 20% moisture), smokeless coal, gas, and oil.

Yes, it complies with the Building Regulations Document J, requiring the increaser to be installed within a masonry chimney.

The Screw-FIX Increaser can handle temperatures up to 600°C (T600 designation).

The connection should be secured using fire cement, ceramic rope, or high-temperature sealant to ensure a gas-tight seal.

No, the increaser must be enclosed within a masonry chimney. Non-masonry enclosures like timber or plasterboard are not acceptable.

The flue system should be inspected and cleaned yearly, but for solid fuel appliances, sweeping twice a year is recommended.
Delivery Information +

We work relentlessly to ensure you get your order fast. Estimated delivery for this product is Friday, April 4th. If you need faster stove or fireplace delivery please give us a call. We can often reduce longer lead times if we pay the carrier £25 for express delivery. Visit our Shipping Information page for more information.

Warranty & Returns +

All our products come with warranties. Mi-Flex offers a lifetime guarantee. Returns for damaged items are covered by insurance; non-damaged returns incur return delivery costs.

Price Match Guarantee +

We will match any price like for like. If you find it cheaper within 48 hours, we'll refund the difference.

Read our buyers guide for this Screw-FIX Increaser - Ø 175-200mm

National Flues Ltd Verdict

The Screw-FIX Increaser - Ø 175-200mm is an exceptional product for ensuring a seamless connection between flue systems. With reliable nationwide delivery and options for both retail and trade customers, National Flues is your go-to supplier for top-quality flue and fireplace components.

The Screw-FIX Increaser is designed to connect a rigid single wall flue system to a flexible flue liner, increasing the diameter by 25mm.

National Flues is a reliable supplier of fireplaces and flue systems, known for competitive prices and dependable nationwide delivery. Catering to both retail and trade customers, National Flues offers secure online payments and trade accounts.

 

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